#include<stdio.h>
#include<stdlib.h>
int main()
{
	int i,j;
	int x=5;
	int y=10;
	
	int height=20;
	int velocity=1;
	
	while(1)
	{
		x=x+velocity;
		system("cls");
		
		
	for(i=0;i<x;i++)
		printf("\n");
	for(j=0;j<y;j++)
		printf(" ");
	printf("o");
	printf("\n");
	
	if(x==height)
		velocity=-velocity;
	if(x==0)
		velocity=-velocity;
	}
	return 0;
}